磁気白矮星からの局所的な熱核爆発
S Scaringi1, P J Groot2,3,4, C Knigge5
1Centre for Extragalactic Astronomy, Department of Physics, Durham University, Durham, UK. simone.scaringi@durham.ac.uk.
Nature
|April 21, 2022
まとめ
天文学者は3つのシステムで 白い矮星に微小な熱核爆発を発見しました これらの現象はX線爆発に似ており 磁気的に閉じ込められた蓄積柱から発生します
科学分野:
- 天文学と天体物理学
- スター進化
- ホワイト・ダワーフ現象
背景:
- クラシックな新星は,白矮星の地球規模の熱核脱出によるものです.
- 白い矮星における局所的な熱核爆発は,中性子星からのX線爆発に類するもので,理論的に予測されている.
- 急速な光学/紫外線の爆発は,白矮星系TV Columbaeで観測されています.
研究 の 目的:
- 白い矮星系で 解明できない爆発の起源を調査する
- これらの爆発のエネルギーと性質を記述し, 既知の天体物理現象と比較する.
- 観測された爆発のための実行可能なメカニズムを提案する.
主な方法:
- TV コロンバ,EI ウルサメジャー,ASASSN-19bhの光学観測.
- 爆発エネルギー,明るさ,および持続時間の分析.
- 観測された爆破特性の理論モデルおよび他の天体物理現象との比較.
主要な成果:
- 3つの白矮星系 (TV Columbae,EI Ursae Majoris,およびASASSN-19bh) で観測された光学爆発.
- マイクロノバと呼ばれるこれらの爆発は クラシックノバの10−6倍ほどのエネルギーを持っています
- I型X線爆発に似たような,急速な明るさの増加と,急速な流出を示します.
結論:
- 蓄積または磁気再接続は,これらの爆発の起源として除外されます.
- 磁気的に閉じ込められた蓄積柱内の熱核の脱出イベントは,マイクロノヴァの原因として提案されています.
- マイクロノバは 恒星爆発の新種で 古典的なノバとは異なります
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